Humanity's choice

Humanity’s choice (via IPCC): Aggressive climate action ASAP (left figure) minimizes future warming. Continued inaction (right figure) results in catastrophic levels of warming, 9°F over much of U.S.

The U.N. Intergovernmental Panel on Climate Change (IPCC) has issued its second of four planned reports examining the state of climate science. This one summarizes what the scientific literature says about “Impacts, Adaptation, and Vulnerability” (big PDF here). As with every recent IPCC report, it is super-cautious to a fault and yet still incredibly alarming.

It warns that we are doing a bad job of dealing with the climate change we’ve experienced to date: “Impacts from recent climate-related extremes, such as heat waves, droughts, floods, cyclones, and wildfires, reveal significant vulnerability and exposure of some ecosystems and many human systems to current climate variability.”